The invention relates to a connector for connecting at least two receptor modules for a liquid medium, by way of example, for the connection of two lines for a liquid medium, wherein the connector includes a first connection end for connection of a first receptor module and a second connection end for the connection of a second receptor module, and wherein the liquid medium is able to flow between the first and second connection ends by means of the connector. The liquid medium in this case may flow from the first to the second connection end, or in the opposite direction, from the second connection end to the first connection end. A receptor module for a liquid medium means, in the framework of the invention, in particular, a line for conducting a liquid medium or a tank for a liquid medium, or a dosing unit for a liquid medium. In this case, a line can also mean a hose line, or a plastic hose. With the use of a connector according to the invention for the connection of at least one line, said connector shall hereinafter be referred to as a line connector. For practical purposes, lines can be inserted in the first connection end or the second connection end of the line connector and preferably be locked in place here.
Line connectors of the type described above are known in the field in different embodiments. In particular with lines and line connectors for the conducting of water or an aqueous medium the problem exists that at low temperatures the liquid medium freezes resulting in volume expansion. Due to said volume expansion, or respectively, because of the resulting pressure, the line and the line connector may be damaged or even fully destroyed.
Numerous measures for the solution of this problem have already been proposed in the field. For the most part, however, these measures are not satisfactory.
In motor vehicles, the so-called SCR method (Selective Catalytic Reduction) is implemented in order to reduce the nitrogen content in the exhaust. In the framework of said SCR method, an aqueous urea solution is used. In particular, with these aqueous urea solutions as well, the problem portrayed above occurs. The aqueous urea solution freezes at low temperatures in a manner analogous to water resulting in volume expansion and as a result of the corresponding pressure increase, lines, connectors and similar items in the SCR system may be damaged or fully destroyed. It is known in the field to empty, by means of a vacuum, the medium conducting lines with these SCR systems after the motor vehicle has been parked. A freezing of the aqueous medium in the lines is thereby eliminated. This method is however, extensive and subject to error.